Particle-hole asymmetry in the dynamical spin and charge responses of corner-shared 1D cuprates

Shaozhi Li,Alberto Nocera,Steven Johnston,Umesh Kumar

doi:10.1038/s42005-021-00718-w

Abstract

Although many experiments imply that oxygen orbitals play an essential role in the high-temperature superconducting cuprates, their precise role in collective spin and charge excitations and superconductivity is not yet fully understood. Here, we study the doping-dependent dynamical spin and charge structure factors of single and multi-orbital (pd) models for doped one-dimensional corner-shared spin-chain cuprates using several numerically exact methods. In doing so, we determine the orbital composition of the collective spin and charge excitations of cuprates, with important implications for our understanding of these materials. For example, we observe a particle-hole asymmetry in the orbital-resolved charge excitations, which is directly relevant to resonant inelastic x-ray scattering experiments and not captured by the single-band Hubbard model. Our results imply that one must explicitly include the oxygen degrees of freedom in order to fully understand some experimental observations on cuprate materials.

Highlights

Many experiments imply that oxygen orbitals play an essential role in the hightemperature superconducting cuprates, their precise role in collective spin and charge excitations and superconductivity is not yet fully understood
Results are shown for determinant quantum Monte Carlo (DQMC)
The pie charts insets show the weight of the Cu, O, and Cu−O components of the moment calculated using d DQMC and e density matrix renormalization group (DMRG)

Summary

Introduction

Many experiments imply that oxygen orbitals play an essential role in the hightemperature superconducting cuprates, their precise role in collective spin and charge excitations and superconductivity is not yet fully understood. While it is clear that the predictions of the single-band Hubbard model are consistent with many experimental observations in the cuprates, recent x-ray scattering and nuclear magnetic resonance experiments have implied that the oxygen 2p orbitals provide important contributions to the spin- and chargeorders[21,22,23]. These observations raise questions on the validity of the single-band Hubbard model for describing some properties of the cuprates, including the fluctuations of their intertwined orders. These calculations are enabled by the fact that 1D systems generally have manageable fermion sign problems[38] and algorithmic advances in computing dynamical response functions using DMRG39,40

Methods

Results

Conclusion